Intelligent Exercise Guidance System Based on Smart Clothing Abstract In this study, we designed and developed an intelligent exercise guidance system based on smart clothing. The system comprised smart clothing for electrocardiogram (ECG) signal acquisition and heart rate (HR) monitoring, an exercise control application program, and a cloud server. Music beats were used to guide the exercise routine. The use of an empirical mode decomposition (EMD)-based ECG signal denoising algorithm and a quadratic polynomial regression model (QPRM) of HR and running cadence (running steps per minute guided by music beats) were proposed for the system. Five types of experiments were conducted: Experiments I and II, R-peak detection; Experiment III, preset QPRMs; Experiment IV, degree of completion of exercises; and Experiment V, comparison of preset and trained QPRMs. The average accuracy and sensitivity of the EMD-based R-peak detection method were respectively 99.8% and 94.87% for ECG data from the MIT-BIH Arrhythmia Database and 96.46% and 98.75% for ECG data collected from university students during the walking exercise. The coefficient of determination and the mean absolute percentage error (MAPE) of the QPRMs were respectively 97.21% and 3.12% for increasing HR and 98.09% and 2.06% for decreasing HR. The average degrees of completion for warmup, training, and cooldown exercise stages were 97.05%, 91.91%, and 98.32%, respectively. The MAPEs of the preset and trained QPRMs were respectively 6.37% and 3.84% for increasing HR and 5.25% and 3.57% for decreasing HR. The experimental results demonstrated the effectiveness of the proposed system in exercise guidance.

Evaluation of Coherence Between ECG and PPG Derived Parameters on Heart Rate Variability and Respiration in Healthy Volunteers With/Without Controlled Breathing Abstract Introduction Photoplethysmography (PPG) is used as a surrogate of electrocardiograms (ECG) for heart rate variability (HRV) analysis or respiratory rate monitoring. PPG is a more convenient way to measure HRV than ECG at rest, since respiration could be a confounding factor in HRV evaluation. However, it remains unclear whether or not controlled breathing affects breath-volume and breathing rate when HRV and pulse rate variability (PRV) are measured in different situations. Consciously controlled breathing was performed to alter the autonomic nervous states of subjects caused by respiratory sinus arrhythmia (RSA). The aim of this study was to investigate the coherence between parameters derived from ECG and PPG on healthy subjects with/without controlled breathing. Method With 30 healthy volunteers, we measured their respiratory frequency and recorded their ECG and PPG signals during spontaneous breathing and controlled breathing, including natural paced breathing, rapid and deep breathing, slow and deep breathing, rapid and shallow breathing, and slow and shallow breathing. Results Obvious coherence was observed between pulse rate and heart rate in both spontaneous breathing and controlled breathing tasks. However, a comparison of PRV and HRV indices demonstrated significant differences during controlled breathing. The results based on time domain and nonlinear method analysis showed that the frequency-dependent changes have more of an impact. The results also indicated that breathing corresponded well in ECG-derived parameters comparing with PPG-derived ones. Conclusion We concluded that PPG-based devices cannot be applied as a precision screening tool to detect HRV, particularly during the cardiopulmonary analysis for the controlled breathing maneuver.

Surgeons’ Operation Skill-Based Control Strategy and Preliminary Evaluation for a Vascular Interventional Surgical Robot Abstract Background Remote vascular intervention surgery that employs surgical robot is an important research field. It is difficult to ensure that the surgical robot realize the surgeons’ operation skills precisely. Objective To solve this problem, surgical robot must be able to duplicate the surgeons’ changeable operation, and guarantee accuracy of synchronous motion between the surgeon’s unpredictable operation and robotic control of surgical tool. Method In this research, the surgeons’ operations were disassembled, eight basic actions were obtained. The surgical robot which can reproduce these basic actions is designed. Further, fuzzy control theory was applied to optimize the remote control and to guarantee the control precision of the synchronous operations. Result Using an experiment, the surgical procedures and operations of interventional surgical robot were obtained and evaluated. The robot can duplicate the surgeons’ operative skills when the control precision of the guidewire is guaranteed. And the axial displacement error of the surgical robot is limited to less than 2 mm. Conclusion The new type of interventional surgical robot was designed and proved that the surgical robot can duplicate the operation skills of the surgeon. The control error of novel surgical robot reaches the accuracy required by the surgeon.

Detection of Emotions Induced by Colors in Compare of Two Nonlinear Mapping of Heart Rate Variability Signal: Triangle and Parabolic Phase Space (TPSM, PPSM) Abstract Purpose Emotions in the word mean understanding, sensing and recognizing something with one’s senses. Emotions are relatively simple responses that the body presents to external or internal stimuli. As the individual’s mental and emotional state changes, the activity of the various parts of the body also changes and increases. This applies to all cultures. So emotion detection from biological signals especially heart rate variability (HRV) signal is considered in this article. Methods The behavior of HRV in two nonlinear phase space have been evaluated and the extracted features of these two mapping have been used for emotion detection. Triangle and Parabolic Phase Space Mapping (TPSM and PPSM) are recently introduced methods which are able to indicate hidden aspects of HRV in response to different emotions. The Lead II of electrocardiogram signal was recorded from 32 female students while they were stimulated by four main psychology colors (blue, green, red, and yellow) to induce emotions which were labeled by SAM test. Results The results show that the mentioned colors caused emotions pleasure, joy, anger, and sadness, respectively. After rating the results by Kruskal–Wallis test, k-nearest neighbor classifier was used for emotion classification. The obtained accuracy after 10-fold cross validation was 90.91%. Conclusions The hypotheses of being a relationship between colors and emotions without awareness of subjects have been proved. Furthermore, by studying the usefulness of TPSM and PPSM as new mapping of HRV, significant results have obtained which indicate the advantages of using them. So it is suggested to use and analyze the usage of these kinds of colors in different psychological situations and for biofeedback tests.

Development of a Direction-Oriented Motion and Short-Sitting and Lying Tai Chi (DOM-SSLTC) Model for Function Recovery in Stroke Patients Abstract Introduction Tai Chi has been shown to have significant benefits in improving muscle strength, balance, and quality of life. The purpose of this study was to design a sitting or lying Tai Chi model with a better playing posture that is easier to play, and with greater exercise efficiency for stroke patients. Methods Eighteen stroke patients were recruited (> 6 months post-stroke; modified Rankin Scale: 2–4). The Direction-Oriented Motion and Short-Sitting and Lying Tai Chi (DOM-SSLTC) model was composed of nine typical Yang-style Tai Chi forms. All the subjects received 12 practice sessions (90 min per session) led by a Tai Chi master, and performed the DOM-SSLTC for 60 min per day for 3 months at home. The characteristics of the exercise patterns were quantified using a Tai Chi master’s motions. National Institutes of Health Stroke Scale, Modified Ashworth Scale, Modified Rankin Scale, Barthel Index, muscle endurance, and psychological evaluations were used to evaluate the effect of the Tai Chi exercise program on the stroke patients. Results The results showed that the rectus femoris and sternocleidomastoid muscles had larger contractions and also had larger trunk flexion in the deep breath with one leg stretched Tai Chi pattern. The 18 stroke patients had significantly decreased Depression Questionnaire scores and improvements in muscle power of knee stretching and sitting up after training. Conclusion This newly developed Tai Chi model with one leg stretched allowed the stroke patients to practice with more intensive exercise, and resulted in improvements in muscle power and depression scale after 3 months exercise.

Contribution of Lower Limb Joint Movement in Adapting to Re-establish Step Length Symmetry During Split-Belt Treadmill Walking Abstract People walking on a split-belt treadmill, where each belt moves at a different speed, adapt step length to re-establish symmetry. However, kinematic changes that occur when re-establishing step length symmetry have not yet been clarified. This study aims to clarify the changing lower limb joint kinematics of each leg when re-establishing step length symmetry. We examined ten young adults who walked on a double-belt treadmill under symmetric and asymmetric conditions of belt velocity using a motion capture system. The results showed that the hip flexion angle at heel strike on one side was not significantly different between the symmetric and asymmetric conditions (p = 0.38) thereby demonstrating that the hip flexion angle of the leading leg re-established symmetry at heel strike (HS) of the fast and slow sides. However, the knee extension angle of the leading leg expanded asymmetrically at HS on both sides. The shank of the fast leg possibly accelerated more to move the heel further forward. The results indicated that subjects with limited knee extension function must increase their hip flexion movement of the fast-side limb to accelerate the shank in the swing phase. The present study suggests securing the range of motion and treatment of the knee extension to reduce the spasticity of hamstrings or plantarflexor before split-belt training. Moreover, split-belt training may be undesirable for improving step length symmetry in impaired subjects who are unlikely to improve the function of knee extension movement. The present study contributes toward developing a rehabilitation protocol that improves the gait asymmetry of patients through split-belt training.

Development of Multi-axis Motor Control Systems for Lower Limb Robotic Exoskeleton Abstract Purpose The aim of this study was to establish a control system with multi-axis motors for a lower limb robotic exoskeleton (LLRE). Methods This LLRE structure was built by using an aluminum alloy designed with an adjustable mechanism. A four-motor control system with four Maxon brushless direct current motors was developed and installed in the hips and knees of the LLRE, respectively. In addition, four harmonic reducers were connected to the motors to increase the torque. A master controller which commands the four-axis motors was developed by using Texas Instruments (TI) embedded chip (TMS320F28069). The walking gait parameters were established to support the LLRE movement. The controller local area network protocol was used to communicate between the master and slave motor controllers. The slave motor controllers were developed by using TI embedded chip (DRV8301/TMS320F28069) for each joint by a high bandwidth control strategy. A high dynamic response system was obtained by considering the LLRE inertia, external variable load induced by the LLRE and delay in a digital control system. Results The result showed that this high bandwidth control with the experimental ones, the trajectory of each joint demonstrated a high response bandwidth and the tracking gait errors were significantly eliminated. Conclusions This study indicated that the development of this LLRE with a master controller/the slave motor controllers strategy through controller local area network protocol was feasible for healthcare applications.

Simplified Tai Chi 6-Form Apparatus for Balance in Elderly People with Alzheimer’s Disease Abstract Background People with Alzheimer’s disease (AD) can have deteriorated walking and impaired postural-balance control, which increases the risk of falls. Tai chi (TC) can improve fitness and balance in elderly people. To facilitate TC learning, we developed the Simplified Tai Chi 6-Form Apparatus (STC6FA). Methods This case-controlled study enrolled 26 elderly people with mild-to-moderate AD. Over 8 weeks, the TC group (TCGr) of 11 elderly people with AD completed a training course for the STC6FA. Another 10 older adults with matched age, height, and severity of dementia were assigned to the control group (CGr). Balance function was measured using a SMART Balance Master (NeuroCom International Inc., OR, USA). The parameters were evaluated three times during the training course, at weeks 0, 4, and 8. Results The balance of both the TCGr and CGr improved significantly. A rhythmic forward–backward shift test revealed more improvement in the TCGr than in the CGr. Conclusion STC6FA training can improve balance and may reduce backward falls in elderly people with mild-to-moderate AD.

Application of Biodegradable Materials in Orthopedics Abstract Purpose To compare the advantages and disadvantages of biodegradable and non-degradable implants in orthopedic fractures. Methods Recent original articles about biodegradable and non-degradable implants for fracture fixation were reviewed extensively, and a comprehensive retrospective analysis was performed. Results Standard orthopedic treatment is to use non-degradable metal implants to fixate the fracture site. This kind of treatment not only causes rejection and stress shielding, but also requires a second surgery to remove the metal implants. In addition, this kind of treatment increases physical pain and is a serious financial burden to patients. However, biodegradable implants do not require a second surgery for removal and have good biocompatibility and osteoconductivity. Conclusions Biodegradable implants do not require a second surgery for removal and have good biocompatibility and osteoconductivity. Consequently, they are an ideal treatment and are increasingly used for orthopedic surgical patients. The most common indications for biodegradable implants include craniofacial reconstruction, anterior cruciate ligament reconstruction, meniscus repair, ankle fracture treatment, and tibia and fibula fracture treatment.

Optimization of Recurrence Quantification Analysis for Detecting the Presence of Multiple Sclerosis Abstract Purpose The visual patterns in recurrence plots of time-series data can be quantified using recurrence quantification analysis (RQA), a phase-space-based method. The ability to quantitate recurrence plots affords the possibility of using them to solve central biomedical problems, for example detecting the presence of neurological diseases. Our goal was to assess this application by statistically comparing the values of plot-based quantifiers of electroencephalograms (EEGs) from patients having multiple sclerosis (MS) with values from the EEGs of control subjects. Methods First, employing a model system consisting of the addition of known deterministic signals to the EEG of normal subjects, we empirically identified the embedding conditions that facilitated detection of the effect of the addition of the signals. Second, we used the conditions thus identified to compare EEGs from 10 patients with MS and 10 age- and gender-matched control subjects, using seven standard recurrence-plot quantifiers. Results We identify embedding dimension of 5 points and time delay of 5 points as conditions that maximize the ability of RQA to detect the presence of deterministic activity in EEGs time series sampled at 500 Hz. The values of the RQA quantifiers computed from the EEGs of the MS patients were significantly greater than the corresponding values from the controls, indicating that the presence of the disease was associated with detectable changes in the EEG (family-wise error < 0.05%). Conclusions Recurrence plots detected the occurrence of alterations in EEGs associated with the presence of MS, indicating a decreased complexity (increased order) of brain electrical activity associated with brain disease.